Integrated suspended stripline structure (SSS) with J-shape defected stripline structure (DSS) to remove undesired signals in wideband applications

An integrated suspended stripline structure with defected stripline structure to produce simultaneous bandpass and notch response is presented and implemented in this paper. The bandpass filter was designed with cascading lowpass and highpass and produced the finite transmission zeros. The integration of SSS bandpass filter with DSS produced high selectivity and attenuation of notch response at resonant frequency of 5.2 GHz and Q-factor of 34.67. The bandpass filter was designed at wideband frequency from 3.1 GHz to 6 GHz with a fractional bandwidth of about 66.67%. The insertion was around 0.1 dB and the return loss was better than 18 dB. The group delay was less than 0.8 ns in the passband, except for the notch response. The design was simulated and fabricated on a Roger Duroid RO4350 with a dielectric constant, ε_r of 3.48 and a thickness of 0.508 mm. The simulation performance showed promising results, which could be further examined in future experimental works. This new class of generalized Chebyshev bandpass filter with DSS is useful to remove any undesired signal in any wideband communication system, particularly in civilian and military radar applications.